Alakazam Star (Crystal Guardians 99)

[Cealgair]

I have Alakazam Star active, and I use the Skill Copy attack, discarding a Pokémon that has two attacks. In the following cases, am I allowed to choose the second attack and make Skill Copy have no effect other than discarding the Pokémon?

1. Alakazam Star has the Energy necessary to use the first attack, but not the second.
2. Alakazam Star has the Energy necessary to use both attacks, but the second one would have no effect (for example, Electrode's (Hidden Legends 5) Mass Destruction if Alakazam Star has any Special Energy attached).
3. Alakazam Star has the Energy necessary to use both attacks, but I cannot use the second one (for example, Meowth's (Steam Siege 88) Stall if it's not my first turn, or a GX attack if I have already used one).

 

[PokePop]

It says right on the card that if you don't have the necessary energy then the attack does nothing.
Also, it says you have to do anything else the attack requires, so if you can't, the attack does nothing.
Other than discarding the Pokemon